The invention relates to a mixing kneader for carrying out mechanical, chemical and/or thermal processes, having at least two rotating shafts with their axes parallel, disk surfaces with kneading bars being provided at least on the one shaft designated as the main shaft, which kneading bars are fitted to the periphery of the disk surfaces and are swept by cleaning and/or kneading and transporting elements which are fitted to the other shaft designated as a stripping shaft.
Such a multi-spindle mixing and kneading machine has been disclosed, for example, in CH-PS 506,322. One shaft thereof is provided with radial disk elements and axially aligned kneading bars arranged between the disks, and is designated as a disk shaft. Kneading elements which are shaped in the manner of frames and are fitted to the second parallel stirrer shaft engage between these disks. These kneading elements clean the disks and kneading bars of the disk shaft.
In order to achieve a reasonably adequate cleaning of the disk surfaces, the stirrer shaft must rotate faster than the disk shaft by a predetermined ratio of the speed of rotation. This ratio of the speed of rotation depends above all on the number of the kneading bars on the disk elements, since the kneading elements must engage in the interspaces between the kneading bars. This results in an inadequate cleaning effect on the disk surfaces, which in turn adversely affects the heat transfer to the product which is to be treated.
Similar comments also apply to a device according to DE-A-2,012,294, EP-A 0,144,092 and CH-A 565,585.
The present invention is based on the object of substantially improving the cleaning of all regions and parts within the mixing kneader and at the same time improving the kneading effect exerted on the product. In a thermal treatment of the product, a further object is to increase the heat exchange area within the mixing kneader and substantially to improve the heat transfer to the product.